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51.
水利工程模型试验计算机测量与控制系统 总被引:1,自引:0,他引:1
采用计算机测量与控制系统应用于水利工程模型试验,设计应用先进的水流循环系统、电磁流量计、电子式电动调节阀、控制接口和软件组成计算机流量闭环自动控制系统;计算机测量与控制系统通过实际使用运行,证明达到了设计指标的要求,大大提高了模型试验测量与控制的精度和工作效率,缩短了模型试验周期,有利于水利工程研究成果质量和科研水平的提高. 相似文献
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53.
本文设置了不同的再生集料替代率,和不同的处理方式,并对试验结果进行了对比和分析,研究了垃圾界面膜化对砂浆强度的影响。结果表明,在取代率相同的情况下,再生骨料经过处理以后其强度最大增加25%,而且随着垃圾砂掺量的增加,砂浆强度呈现出总体下降的趋势。 相似文献
54.
A micromechanical approach based on a two-layer built-in model and a numerical simulation based on boundary element method are proposed to predict the effective properties of the multi-inclusion composite with imperfect interfaces.The spring model is introduced to simulate the interface imperfection.These two methods are compared with each other,and good agreement is achieved.The effects of interface spring stiffness,volume ratio and stiffness of inclusions on the micro-and macro-mechanical behaviors of fib... 相似文献
55.
56.
以广东某核电工程为例,阐明了设计过程中接口的有效管理的重要作用,简要介绍了在核电工程设计中应用接口控制手册(ICM)进行设计接口的管理的特点.同时就目前接口管理的实施情况及在后续的核电工程设计中如何更有效的进行接口管理,提出了几点建议和看法. 相似文献
57.
电力通信标准信息服务平台的需求和构想 总被引:1,自引:0,他引:1
文章以体现电力通信专业特色为主线,对建立各单位通信专业共享的、统一的、标准检索/管理/维护一体化信息服务平台的建设进行了目标分析、需求分析和功能分析。重点探讨了平台的安全策略、数据库架构、跨平台检索、界面设计、服务和管理等方面的内容,希望能为电力通信专业标准化活动和电力通信标准信息服务平台的建设工作提供决策参考。 相似文献
58.
Min Yan Jia‐Yan Liang Tong‐Tong Zuo Ya‐Xia Yin Sen Xin Shuang‐Jie Tan Yu‐Guo Guo Li‐Jun Wan 《Advanced functional materials》2020,30(6)
Solid polymer electrolytes (SPEs) are promising candidates for developing high‐energy‐density Li metal batteries due to their flexible processability. However, the low mechanical strength as well as the inferior interfacial regulation of ions between SPEs and Li metal anode limit the suppress ion of Li dendrites and destabilize the Li anode. To meet these challenges, interfacial engineering aiming to homogenize the distribution of Li+/electron accompanied with enhanced mechanical strength by Mg3N2 layer decorating polyethylene oxide is demonstrated. The intermediary Mg3N2 in situ transforms to a mixed ion/electron conducting interlayer consisting of a fast ionic conductor Li3N and a benign electronic conductor Mg metal, which can buffer the Li+ concentration gradient and level the nonuniform electric current distribution during cycling, as demonstrated by a COMSOL Multiphysics simulation. These characteristics endow the solid full cell with a dendrite‐free Li anode and enhanced cycling stability and kinetics. The innovative interface design will accelerate the commercial application of high‐energy‐density solid batteries. 相似文献
59.
Indranil Mondal Hyunhwa Lee Heeyoung Kim Jeong Young Park 《Advanced functional materials》2020,30(11)
Precise control of the topology of metal nanocrystals and appropriate modulation of the metal–semiconductor heterostructure is an important way to understand the relationship between structure and material properties for plasmon‐induced solar‐to‐chemical energy conversion. Here, a bottom‐up wet chemical approach to synthesize Au/Ni2P heterostructures via Pt‐catalyzed quasi‐epitaxial overgrowth of Ni on Au nanorods (NR) is presented. The structural motif of the Ni2P is controlled using the aspect ratio of the Au NR and the effective micelle concentration of the C16TAB capping agent. Highly ordered Au/Pt/Ni2P nanostructures are employed as the photoelectrocatalytic anode system for water splitting. Electrochemical and ultrafast absorption spectroscopy characterization indicates that the structural motif of the Ni2P (controlled by the outer‐shell deposition of Ni) helps to manipulate hot electron transfer during surface plasmon decay. With optimized Ni2P thickness, Pt‐tipped Au NR with an aspect ratio of 5.2 exhibits a geometric current density of 10 mA cm?2 with an overpotential of 140 mV. The photoanode displays unprecedented long‐term stability with continuous chronoamperometric performance of 50 h at an input potential of 1.5 V with over 30 days. This work provides definitive guidance for designing plasmonic–catalytic nanomaterials for enhanced solar‐to‐chemical energy conversion. 相似文献
60.
Wenshu Chen Jiajun Gu Yongping Du Fang Song Fanxing Bu Jinghan Li Yang Yuan Ruichun Luo Qinglei Liu Di Zhang 《Advanced functional materials》2020,30(25)
Large‐scale production of hydrogen from water‐alkali electrolyzers is impeded by the sluggish kinetics of hydrogen evolution reaction (HER) electrocatalysts. The hybridization of an acid‐active HER catalyst with a cocatalyst at the nanoscale helps boost HER kinetics in alkaline media. Here, it is demonstrated that 1T–MoS2 nanosheet edges (instead of basal planes) decorated by metal hydroxides form highly active / heterostructures, which significantly enhance HER performance in alkaline media. Featured with rich / sites, the fabricated 1T–MoS2 QS/Ni(OH)2 hybrid (quantum sized 1T–MoS2 sheets decorated with Ni(OH)2 via interface engineering) only requires overpotentials of 57 and 112 mV to drive HER current densities of 10 and 100 mA cm?2, respectively, and has a low Tafel slope of 30 mV dec?1 in 1 m KOH. So far, this is the best performance for MoS2‐based electrocatalysts and the 1T–MoS2 QS/Ni(OH)2 hybrid is among the best‐performing non‐Pt alkaline HER electrocatalysts known. The HER process is durable for 100 h at current densities up to 500 mA cm?2. This work not only provides an active, cost‐effective, and robust alkaline HER electrocatalyst, but also demonstrates a design strategy for preparing high‐performance catalysts based on edge‐rich 2D quantum sheets for other catalytic reactions. 相似文献